Embolic protection device

Abstract

An embolic protection device is provided that includes a hollow rail and a filter basket attached to the hollow rail. The filter basket includes a vessel wall conforming portion, a tapered portion, and an emboli collection portion. The vessel wall conforming portion of the filter basket has an expanded diameter that is greater than a diameter of a target blood vessel. The tapered portion is attached to the vessel wall conforming portion and decreases in diameter in a downstream direction of blood flow of the target blood vessel. The emboli collection portion has an open end attached to the tapered portion and a closed end attached to the hollow rail, and the emboli collection portion has a diameter that is less than a diameter of the target blood vessel. The filter basket is configured to shunt blood flow through the tapered portion when blood flow through the emboli collection portion is obstructed.

Description

Technical Field

[0001] This disclosure generally relates to medical devices for endovascular surgery, and more specifically, to embolism protection devices configured to maintain uninterrupted blood flow while capturing emboli. Background Technology

[0002] Endovascular surgeries, such as angioplasty, stent placement, and thrombectomy, typically involve inserting devices inside a blood vessel. While these procedures are beneficial, they carry the risk of creating emboli—small particles or blood clots that can move in the bloodstream. If these emboli are allowed to travel downstream, they can block blood vessels, leading to serious health conditions such as heart attacks, strokes, or pulmonary embolisms. The severity of these conditions depends on the blood vessel from which the embolism originates and its subsequent destination.

[0003] To reduce the risk of embolism, embolic protection devices are commonly used. These devices typically consist of a filter placed inside the blood vessel to capture any emboli that may form during the procedure. The filter is designed to allow blood to flow while capturing the emboli and preventing them from moving downstream.

[0004] However, a challenge these devices face is maintaining sufficient blood flow through the filter when it becomes clogged with emboli. Embolism buildup can lead to a significant reduction or even complete blockage of blood flow through the filter. This can pose health risks to patients, especially when the filter is placed in a vessel supplying blood to major organs. Furthermore, reduced or blocked blood flow can prevent additional emboli from being effectively delivered to the filter for capture, potentially causing them to remain suspended in the vessel at points of blood stagnation. Summary of the Invention

[0005] According to one aspect of the present invention, an embolism protection device is provided, comprising a hollow guide rail and a filter basket attached to the hollow guide rail. The filter basket includes a vessel wall-adhering portion, a tapering portion, and an embolus-collecting portion. The vessel wall-adhering portion of the filter basket has an expansion diameter larger than the diameter of a target vessel. The tapering portion is attached to the vessel wall-adhering portion and decreases in diameter in the downstream direction of blood flow in the target vessel. The embolus-collecting portion has an open end attached to the tapering portion and a closed end attached to the hollow guide rail, and the diameter of the embolus-collecting portion is smaller than the diameter of the target vessel. The filter basket is configured to divert blood flow through the tapering portion when blood flow through the embolus-collecting portion is obstructed.

[0006] The filter basket may also include a stiffening member attached between the vessel wall fitting portion and the hollow guide rail. The stiffening member may be defined by a portion of the filter basket coated with a polymer or metal. Alternatively, the stiffening member may be formed by attaching an auxiliary component to the vessel wall fitting portion.

[0007] The diameter of the embolus collection portion at the interface with the tapering portion can be 60% or less of the expansion diameter of the portion adhering to the vessel wall.

[0008] The diameter of the embolus collection portion at the interface with the tapering portion may be 50% or less of the expansion diameter of the portion adhering to the vessel wall.

[0009] The length of the embolus collection section may be at least twice the combined length of the stiffening enhancement component, the vessel wall fitting section, and the tapering section.

[0010] The length of the embolus collection section may be at least two and a half times the combined length of the stiffening enhancement component, the vessel wall fitting section, and the tapering section.

[0011] The filter basket can be made of woven material or sheet fabric with pores formed therein. The filter basket can also be made of metal, fabric, or polymer, or a combination of two or more of these.

[0012] The filter basket can be compressible and made of shape memory material. The shape memory material can be nitinol.

[0013] The embolism protection device may also include a radiopaque filling mark on the embolism collection section of the filter basket.

[0014] The hollow guide rail can be configured to deliver along a guidewire that can be inserted into the target blood vessel. Attached Figure Description

[0015] The above and other aspects and features of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: Figure 1 This is a schematic diagram of an existing embolization protection filter in a blood vessel; Figure 2 This is a schematic diagram of an embolism protection device according to an embodiment of the present invention; and Figure 3 These are photographic images of an embolism protection device according to an embodiment of the present invention. Detailed Implementation

[0016] In the following detailed description, representative embodiments with specific details disclosed are set forth for purposes of explanation and not limitation, in order to provide a thorough understanding of the teachings. However, it will be apparent to those skilled in the art who benefit from this disclosure that other embodiments, departing from the specific details disclosed herein, remain within the scope of the appended claims. Furthermore, descriptions of well-known apparatuses and methods may have been omitted to avoid obscuring the description of the exemplary embodiments. These methods and apparatuses are clearly within the scope of the teachings. Additionally, throughout the drawings, the same reference numerals refer to the same or similar elements.

[0017] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. The defined terminology complements the technical and scientific meaning of the defined terminology as commonly understood and accepted in the art as taught herein. As used in the specification and appended claims, the terms “a,” “an,” and “the” include both singular and plural referents unless the context clearly indicates otherwise. Thus, for example, “an apparatus” includes one apparatus and multiple apparatuses. Furthermore, for example, when an element is described as being “connected to” another element, that one element may be directly connected to the other element or indirectly connected to the other element in an operative manner.

[0018] This disclosure relates to medical devices for endovascular procedures, and more specifically to embolism protection devices. These devices are designed to capture emboli, small particles or blood clots that can move in the bloodstream, during endovascular procedures. The captured emboli are prevented from moving downstream, where they could block blood vessels and lead to serious health conditions.

[0019] The design and geometry of the filter play a crucial role in its performance. A filter typically includes a collection basket in which emboli are captured. The collection basket is designed to conform to the vessel wall to ensure that no emboli can bypass the filter. The collection basket can be made of a variety of materials, including metals, fabrics, or polymers, and can be constructed in woven or mesh patterns. Some filters may also contain shape memory materials, such as nitinol, which can return to their original shape after being compressed for delivery into the blood vessel.

[0020] The embolism protection device of this invention includes a specially designed collection basket or filter basket. The filter basket may have a larger diameter portion on the inflow side to ensure proper fit against the vessel wall and resist displacement. The filter basket can then taper to a smaller diameter where the embolus accumulates. This design allows blood to flow around the collected embolus, maintaining adequate blood flow throughout the procedure even if the filter basket is full.

[0021] The material composition of the filter basket is not limited and may include metal, fabric, polymer, or combinations thereof. For example, the filter basket may be made of a woven material. As another example, the filter basket may be made of fabric with small pores formed therein. In some embodiments, the filter basket is made of a shape memory material such as nitinol, which is able to return to its original shape after being compressed for delivery into the blood vessel.

[0022] The embolism protection device may also include a stiffening component attached to the hollow guide rail. This component can be formed by selectively coating the filter basket with a polymer or metal in the portion of the filter basket that fits against the vessel wall. Alternatively, the stiffening component can be formed by attaching auxiliary components such as laser-cut structures or auxiliary braided structures to the portion of the filter basket that fits against the vessel wall.

[0023] In some embodiments, the embolism protection device may include radiopaque filling marks on the embolus collection section of the filter basket. These marks are visible on X-ray imaging and alert the physician when an embolus load approaches the taper of the filter inlet section. This feature helps ensure that the filter does not fill beyond the area around which blood flow can bypass the collection section, which would impair the design's ability to maintain blood flow.

[0024] Figure 1 A schematic diagram of a prior art embolization protection filter within a blood vessel is depicted. The vessel wall 1 is shown, with blood flow direction 2 moving towards the prior art filter geometry 3. An embolus 4 is illustrated as accumulating within the filter, resulting in obstructed blood flow 5 and reduced blood flow 6 around the filter. In some cases, as described above, the filter geometry 3 may fail to maintain sufficient blood flow due to the accumulation of emboli 4. This can lead to reduced or complete blockage of blood reaching downstream organs, as well as stagnation of blood flow before the filter, both of which can pose health risks to the patient.

[0025] Figure 2 This is a schematic diagram of an embolism protection device 100 according to an embodiment of the present invention within a blood vessel. The blood vessel wall 1 is shown, and the blood flow direction 2 is indicated by the arrows shown.

[0026] like Figure 2 As shown, the device includes a portion that engages with the vessel wall 1, a portion that tapers inward toward the vessel's central axis, and a portion with a diameter smaller than that of the portion engaging with the vessel wall 1. The smaller diameter portion is used to capture the embolus 4 within the embolism protection device 100. Simultaneously, the tapering portion allows blood flow 7 to bypass the accumulated embolus 4. This innovative filter geometry ensures that blood can continue to flow past the embolus 4, preventing blockage and maintaining circulation during endovascular procedures.

[0027] Figure 3 This is a photographic image of an embolism protection device 100 according to an embodiment of the present invention.

[0028] refer to Figure 3 The device 100 includes a hollow guide rail 101. The hollow guide rail 101 supports the remaining components of the device (collectively referred to herein as a filter basket) and allows the device to be delivered along the guidewire 107 for positioning and removal from the target blood vessel. Using tools known in the art, the guide rail 101 can be delivered along the guidewire within the catheter to ensure accurate placement and retrieval of the device 100. Here, the filter basket described below is compressed during delivery within the catheter and then expands upon deployment and release from the catheter. Figure 3 The state shown. In some respects, the dimensions of the hollow guide rail 101 allow other interventional devices to be guided around (above the guidewire), beside (monorail), or inside it.

[0029] Attached to the upstream hub 101a of the hollow guide rail 101 is a stiffening member 102, which provides structural support and helps maintain the device's position against the blood vessel wall. In some cases, the stiffening member 102 can be formed by selectively coating the proximal (upstream) portion of the filter basket with a polymer or metal. In other cases, the stiffening member 102 can be formed by attaching auxiliary components, such as laser-cut structures or auxiliary braided structures, between the hollow guide rail 101 and the blood vessel wall-fitting portion 103 of the filter basket. Regardless of its composition, the stiffening member 102 is permeable to blood and emboli, allowing both to flow downstream into the remainder of the filter basket.

[0030] Attached to the stiffness-enhancing component 102 is the vessel wall-fitting portion 103 of the filter basket. The vessel wall-fitting portion 103 is configured to form a seal against the vessel wall, preventing emboli from bypassing the filter basket. The expansion diameter of the vessel wall-fitting portion 103 is larger than the vessel diameter, thereby applying an outward force to the vessel wall and holding the device 100 in place within the vessel. In some aspects, auxiliary components may be attached to the vessel wall-fitting portion 103 of the filter basket to increase the outward force, further ensuring a seal against the vessel wall 1. The permeability of the vessel wall-fitting portion 103 to blood and emboli is unrestricted because it is pressed against the vessel wall.

[0031] The portion 104 attached to the vessel wall is tapered. As shown in the figure, the diameter of the tapered portion 104 decreases in the downstream direction of blood flow within the vessel. The tapered portion 104 is permeable to downstream flowing blood but impermeable to emboli.

[0032] Attached to the tapering portion 104 is the embolus collection portion. Like the tapering portion 104, the embolus collection portion is permeable to downstream flowing blood, but impermeable to emboli.

[0033] The embolus collection section 105 of the filter basket is where the embolus 4 is captured and collected. Simultaneously, the tapered section 104 allows blood flow to bypass the accumulated embolus 4. This innovative filter geometry ensures that blood can continue to flow past the embolus, preventing blockages and maintaining circulation during endovascular procedures.

[0034] In some cases, the filter basket, including the vessel wall-adhering portion 103, the tapering region 104, and the embolus collection portion 105, may be made of a woven material, a sheet material with pores formed therein, or a shape memory material such as nitinol. The material used for the filter basket may be metal, fabric, or polymer. It should be understood that the pore size through the tapering region 104 and the embolus collection portion 105 is designed to allow blood to pass through but prevent emboli from passing through.

[0035] At the distal end of the device, the tapered / closed end 106 of the filter basket is secured to the downstream hub 101b of the hollow guide rail 107 to prevent the embolus 4 from escaping. From there, the hollow guide rail 101 can continue to extend for a certain distance. As previously described, the hollow guide rail 101 extends along the guidewire device 107 to facilitate its navigation in the vascular system in a manner known in the art.

[0036] It should be understood that the size of the embolization protection device will depend on the diameter of the target blood vessel to which it is intended to be used and the size of the particles to be captured. Nevertheless, to provide some dimensional background, some example dimensions of device components are provided below. It is emphasized here that the inventive concept is not limited to these specific examples, nor is it limited to components having the relative dimensions shown in the examples.

[0037] For example, in the case of intravenous use, where the vein is relatively large, the vessel wall fitting portion 103 can expand to a diameter of 33 mm, while the diameter of the embolus collection portion 105 can be 12 to 16 mm. In this case, the combined length of the stiffness-enhancing component 102, the vessel wall fitting portion 103, and the tapering portion 104 can be 40 mm, and the length of the embolus collection portion 105 can be 100 mm. The length of the hollow guide rail 101 can be approximately 200 cm.

[0038] In some exemplary embodiments of the present invention, the diameter of the embolus collection portion 105 at its interface with the tapering portion 104 is 60% or less of the expansion diameter of the vessel wall adhering portion 103. In other embodiments, the diameter of the embolus collection portion 105 at its interface with the tapering portion 104 is 50% or less of the expansion diameter of the vessel wall adhering portion 103.

[0039] Furthermore, in some exemplary embodiments of the present invention, the length of the embolus collection portion 105 is at least twice the combined length of the stiffness-enhancing member 102, the vessel wall-adhering portion 103, and the tapering portion 104. In other embodiments of the present invention, the length of the embolus collection portion 105 is at least two and a half times the combined length of the stiffness-enhancing member 102, the vessel wall-adhering portion 103, and the tapering portion 104.

[0040] In some aspects, the device may include a radiopaque filling mark on the plug collection portion 105 of the filter basket, which is visible under X-ray imaging. These are made by Figure 3 The superimposed white dots 108 in the image indicate this. These markings alert the physician when the embolus load approaches the taper of the inflow portion of the embolus collection section 105, indicating that the filter may need to be emptied before continuing the procedure. This feature helps ensure that the filter does not fill beyond the area that the collection section 105 is capable of shunting blood flow, which would impair its ability to maintain blood flow.

[0041] In some embodiments, the vessel wall lining portion 103, the tapered portion 104, and the embolus collection portion 105 are formed from a single continuous braided material. However, it should be understood that two or more of these portions may be formed from separate materials and then attached together.

[0042] Although the invention has been illustrated and described in detail in the accompanying drawings and foregoing description, such illustrations and descriptions should be considered illustrative or exemplary rather than restrictive; the invention is not limited to the disclosed embodiments. Other variations of the disclosed embodiments can be understood and implemented by those skilled in the art in practicing the claimed invention by studying the drawings, the disclosure, and the appended claims. While representative embodiments have been disclosed herein, those skilled in the art will understand that many variations are possible in accordance with these teachings and remain within the scope of the appended claims. Therefore, the invention is not limited except within the scope of the appended claims.

Claims

1. An embolism protection device, comprising a hollow guide rail and a filter basket attached to the hollow guide rail, the filter basket comprising: A portion of the vessel wall that adheres to the vessel wall with an expansion diameter greater than that of the target vessel. A tapered portion attached to the blood vessel wall, wherein the diameter of the tapered portion decreases in the downstream direction of the blood flow in the target blood vessel; as well as The device includes an embolus collection portion having an open end attached to the tapered portion and a closed end attached to the hollow guide rail, wherein the diameter of the embolus collection portion is smaller than the diameter of the target blood vessel. The filter basket is configured to divert blood flow through the constricted portion when blood flow through the embolus collection portion is obstructed.

2. The embolic protection device according to claim 1, wherein, The filter basket also includes a stiffening component attached between the portion that fits against the blood vessel wall and the hollow guide rail.

3. The embolic protection device according to claim 2, wherein, The stiffness-enhancing component is defined by a portion of the filter basket coated with a polymer or metal.

4. The embolic protection device according to claim 1, wherein, The diameter of the embolus collection portion at the interface with the tapering portion is 60% or less of the expansion diameter of the portion adhering to the blood vessel wall.

5. The embolic protection device according to claim 1, wherein, The diameter of the embolus collection portion at the interface with the tapering portion is 50% or less of the expansion diameter of the portion adhering to the vessel wall.

6. The embolic protection device according to claim 2, wherein, The length of the embolus collection section is at least twice the combined length of the stiffening-enhancing component, the vessel wall-adhering portion, and the tapering portion.

7. The embolic protection device according to claim 2, wherein, The length of the embolus collection section is at least two and a half times the combined length of the stiffening-enhancing component, the vessel wall-adhering portion, and the tapering portion.

8. The embolic protection device according to claim 2, wherein, The stiffness-enhancing component is formed by attaching an auxiliary component to the blood vessel wall fitting portion.

9. The embolic protection device according to claim 1, wherein, The filter basket is made of woven material.

10. The embolic protection device according to claim 1, wherein, The filter basket is made of a sheet-like fabric with pores formed therein.

11. The embolic protection device according to claim 4, wherein, The filter basket is made of metal, fabric, polymer, or a combination of two or more of them.

12. The embolic protection device according to claim 1, wherein, The filter basket is compressible and made of shape memory material.

13. The embolic protection device according to claim 12, wherein, The shape memory material is nickel-titanium.

14. The embolism protection device according to claim 1, further comprising a radiopaque filling mark on the embolus collection portion of the filter basket.

15. The embolic protection device according to claim 1, wherein, The hollow guide rail is configured to deliver along a guidewire that can be inserted into the target blood vessel.

Images